Move parsing of the size property from computed_values to validation.

weasy/css/computed_values.py

@@ -126,6 +126,10 @@ PAGE_SIZES = dict(
         17 * LENGTHS_TO_PIXELS['in'],
     ),
 )
+for w, h in PAGE_SIZES.values():
+    assert w < h
+
+INITIAL_VALUES['size'] = PAGE_SIZES['A4']
 
 
 class Computer(object):
@@ -212,6 +216,7 @@ def other_color(computer, name, value):
 
 @Computer.register('background-position')
 @Computer.register('border-spacing')
+@Computer.register('size')
 def length_list(computer, name, values):
     """Compute the properties with a list of lengths."""
     return [length(computer, name, value) for value in values]
@@ -403,49 +408,6 @@ def line_height(computer, name, value):
     return factor * font_size_value
 
 
-@Computer.register('size')
-def size(computer, name, values):
-    """Compute the ``size`` property.
-
-    See CSS3 Paged Media.
-
-    """
-    if computer.element != '@page':
-        return 'none'
-
-    keywords = map(get_keyword, values)
-    values = length_list(computer, name, values)
-
-    if keywords == ['auto']:
-        keywords = ['A4']  # Chosen by the UA. (That’s me!)
-
-    if isinstance(values[0], (int, float)):
-        if len(values) == 2:
-            assert isinstance(values[1], (int, float))
-            return values
-        else:
-            # square page
-            value, = values
-            return value, value
-    else:
-        orientation = None
-        size_value = None
-        for i, keyword in enumerate(keywords):
-            if keyword in ('portrait', 'landscape'):
-                orientation = keyword
-            elif keyword in PAGE_SIZES:
-                size_value = keyword
-            else:
-                raise ValueError("Illegal value for 'size': %r" % values[i])
-        if size_value is None:
-            size_value = 'A4'
-        width, height = PAGE_SIZES[size_value]
-        if (orientation == 'portrait' and width > height) or \
-               (orientation == 'landscape' and height > width):
-            width, height = height, width
-        return width, height
-
-
 @Computer.register('text-align')
 def text_align(computer, name, value):
     """Compute the ``text-align`` property."""

weasy/css/properties.py

@@ -114,7 +114,7 @@ INITIAL_VALUES = {
     'z_index': 'auto',
 
     # CSS3 Paged Media: http://www.w3.org/TR/css3-page/#page-size
-    'size': _parse('auto'),
+    'size': None,  # XXX set to A4 in computed_values
 
     # CSS3 User Interface: http://www.w3.org/TR/css3-ui/#box-sizing
     'box_sizing': 'content-box',

weasy/css/validation.py

@@ -599,26 +599,38 @@ def size(values):
     See http://www.w3.org/TR/css3-page/#page-size-prop
 
     """
-    if len(values) == 1:
-        if is_dimension(values[0]):
-            return values
-        keyword = get_single_keyword(values)
-        if (keyword in ('auto', 'portrait', 'landscape') or
-                keyword in computed_values.PAGE_SIZES):
-            return values
-    if len(values) == 2:
-        if all(is_dimension(value) for value in values):
-            return values
-        keywords = map(get_keyword, values)
-        if (
-            keywords[0] in ('portrait', 'landscape') and
-            keywords[1] in computed_values.PAGE_SIZES
-        ) or (
-            keywords[0] in computed_values.PAGE_SIZES and
-            keywords[1] in ('portrait', 'landscape')
-        ):
+    if is_dimension(values[0]):
+        if len(values) == 1:
+            return values * 2
+        elif len(values) == 2 and is_dimension(values[1]):
             return values
 
+    keywords = map(get_keyword, values)
+    if len(keywords) == 1:
+        keyword = keywords[0]
+        if keyword in ('auto', 'portrait'):
+            return INITIAL_VALUES['size']
+        elif keyword == 'landscape':
+            height, width = INITIAL_VALUES['size']
+            return width, height
+        elif keyword in computed_values.PAGE_SIZES:
+            return computed_values.PAGE_SIZES[keyword]
+
+    if len(keywords) == 2:
+        if keywords[0] in ('portrait', 'landscape'):
+            orientation, size = keywords
+        elif keywords[1] in ('portrait', 'landscape'):
+            size, orientation = keywords
+        else:
+            size = None
+        if size in computed_values.PAGE_SIZES:
+            size = computed_values.PAGE_SIZES[size]
+            if orientation == 'portrait':
+                return size
+            else:
+                height, width = size
+                return width, height
+
 
 # Expanders